The present invention relates to a system (apparatus), and a storage medium, for retrieving secure information from a local database for temporary storage, printing and usage by an information user.
Systems for storage and retrieval of secure information are well known in the art. As used herein, the term "secure information" is intended to mean information (alphanumeric data, graphics and the like) which is either encrypted or otherwise protected to prevent access thereto except by an authorized user. Such systems have been proposed and are employed both for the case where the information source (database) is centralized, and for the case where the information source has been distributed to multiple users. In the latter case, CD-ROMs have been used to export databases to multiple users so that information storage and retrieval takes place at the user site.
In the U.S. Pat. No. 5,010,571 to Ron Katznelson and the U.S. Pat. Nos. 4,827,508, 4,977,594 and 5,050,213 to Victor Shear, it is proposed to provide encrypted digital information on CD-ROMs at the user site and to monitor and account for each item or "packet" of information which is retrieved and decrypted from a CD-ROM by an authorized user.
This concept of retrieving information on a "pay-as-you-go" basis is also disclosed in the U.S. Pat. No. 5,247,575 of Peter J. Sprague and Thomas H. Lipscomb to include individual access to encrypted data which is "broadcast" to multiple user sites from a central source and/or to provide individual access to encrypted data stored at a central source, using conventional time sharing techniques and transmission via telephone dial-up or local area network (LAN) or wide area network (WAN) communication.
All of these prior art systems permit the user's access to the secure information to be monitored and strictly controlled. This is accomplished, in practice, by maintaining a record at each user site of each information packet that is retrieved as well as the cost thereof to the user, and then "polling" all user sites from a remote central site, on a regular basis, to retrieve the user data and, if necessary, disable the equipment at one or more user sites to prevent further access to the secure information at these sites.
Systems of the type require a confidential "decryption key" to enable the decryption of the encrypted information using a standard or a specialized decryption algorithm. As used herein, the term "decryption key" or simply "key" is intended to mean a series of numbers or characters which, when utilized in a decryption algorithm, decrypts encrypted data.
In the aforementioned patents it has been proposed to transmit these keys to each user site on a regular basis, provided that the user's financial account is up-to-date. If a user workstation does not receive a new key before the previous key expires, the ability of the workstation to decrypt information from CD-ROMs will terminate.
Needless to say, transmitting new keys to each user workstation, even at six month intervals, is a time consuming task and such transmission is subject to interception and attack by persons who would attempt to obtain free and unfettered access to the encrypted information.
Furthermore, the use of a single key to gain access to all encrypted information on one or more CD-ROMs is fraught with danger. If this single key were discovered or "reverse engineered", all encrypted information on the CD-ROM's would become available to persons who may have no intention of paying for it.